The present invention relates to organic soluble wholly aromatic polyamides, and in particular to wholly aromatic polyamides prepared by the polycondensation reaction of 1,4-naphthyl or 2,6-naphthyl containing diacids and aromatic diamines.
Wholly aromatic polyamides (aramides) are characterized as highly thermal stable polymers with a favorable balance of physical and chemical properties. However, these polymers are generally intractable and lack the properties essential for successful fabrication into useful forms such as films and fibers due to their high melting or glass transition temperature and their limited solubility in organic solvents. For example, polyamides or polyimides having the structures indicated below generally have high glass transition temperatures (T.sub.g) and melting points (T.sub.m), and accordingly can not easily be fabricated into films or fibers. ##STR1##
Some melt processable linear polyimides having structures indicated below have been developed. ##STR2##
These polyimides have superior thermal stability, chemical resistance, dimension stability, mechanical properties and electrical properties. However, their solubility in organic solvents is still low and accordingly they are not suitable for being fabricated into films or fibers.